Vehicle seat suspension with omni directional isolator

Abstract

A vehicle seat suspension apparatus that is mechanically simple, inexpensive, occupies little space, and operates effectively with force inputs from any horizontal direction. The preferred embodiment includes a base, an isolator, and a plurality of links connected to both the base and isolator so that the isolator is suspended from the base and can move or swing horizontally in all directions relative to the base. The isolator has an upper plate with two flanges that depend from the plate. The base is positioned directly below the upper plate and between the two flanges. The links are connected to the base and the flanges of the isolator by means of ball and socket connectors that permit the isolator to move in all horizontal directions relative to the base.

Description

BACKGROUND OF THE INVENTION

The present invention relates generally to vehicle seat suspension. More particularly, the invention relates to a vehicle seat suspension which incorporates a new and unique isolation system for reducing the transmission of horizontally directed forces to the seat occupant.

For many years, it has been common practice to provide vehicle seats with some form of "isolation" system. So called "fore and aft" isolators have been employed to reduce the undesirable effects of forces inputted to the seat from the front or back. So too, "lateral" isolators have been used for the same purpose with respect to forces input from the sides of the vehicle. Oftentimes, both fore/aft and lateral isolators are used together. The combined systems, however, are less than satisfactory. First they are relatively complex mechanically and are therefore expensive both to manufacture and install. Second, with space constraints becoming increasingly severe, these combined systems tend to present too high a profile. Lastly, they tend to react along the fore and aft or lateral axes and therefore do not react as effectively to angular inputs. It would be desirable therefore to provide a truly omni directional isolator that is simple in construction, inexpensive to manufacture, effective in attenuating forces input from all directions, and occupies a relatively small space envelope.

SUMMARY OF THE INVENTION

The present invention is directed to a vehicle seat suspension apparatus that achieves the aforementioned goals. It is relatively small, mechanically simple, inexpensive, and operates effectively with force inputs from any horizontal direction. The invention comprises a base, an isolator, and a plurality of links connected to both the base and isolator so that the isolator is suspended from the base and can move or swing horizontally in all directions relative to the base.

In the illustrated preferred embodiment the isolator is constructed with an upper plate having two flanges that depend from the plate. The base is positioned directly below the upper plate and between the two flanges. The links are connected to the base and the flanges of the isolator by means of ball and socket connectors that permit the isolator to move in all horizontal directions relative to the base.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features which are characteristic of the present invention are set forth in the appended claims. However, the invention's preferred embodiments, together with further objects and attendant advantages, will be best understood by reference to the following detailed description taken in connection with the accompanying drawings in which:

FIG. 1 is a perspective view of one preferred embodiment of the present invention;

FIG. 2 is another perspective view of the preferred embodiment illustrated in FIG. 1 with the isolator plate removed to show details of construction;

FIG. 3 is a side view of the same preferred embodiment shown in FIG. 1;

FIG. 4 is an enlarged cross-section view of certain components circled in FIG. 3;

FIGS. 5 and 6 are end views of the embodiment of FIG. 1, showing respectively centered and displaced positions of the isolator; and

FIG. 7 is an enlarged perspective view, in partial cross-section, illustrating one preferred link mechanism useful in the practice of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to the drawings, a vehicle seat suspension apparatus is illustrated in one preferred form and designated generally as 10. The suspension apparatus 10 includes, as basic components, a base 12, an isolator 14 and a plurality of links 16 which are used to suspend the isolator from the base.

The base 12 may take many forms well known to those skilled in the art. In the illustrated embodiment the base has a lower platform 20 and an upper platform 22 mounted to permit vertical movement of the two platforms relative to one another. The mechanism that provides this vertical movement functionality is shown to be a conventional scissors linkage 24, although many other designs may be employed. As the following description will make clear, the base may comprise any suitable structure that will accommodate the links 16 and support the isolator suspended from it. To that end, the upper platform includes a plurality of fixtures 26 that support the connector to which the links 16 are assembled.

The isolator 14 comprises an upper plate 28, to which the seat is mounted in any conventional manner, and a pair of flanges 30 depending from opposing sides of plate 28. Fixtures 32 are located adjacent the bottom edges of the flanges and serve to support the connector to which the links 16 are assembled. The upper plate 28 and flanges 30 are dimensioned so that the base platform 22 may be positioned under the plate and between the flanges, as shown. The flanges 30 also have apertures or cutouts 34 located at the point where the links are connected to the flanges. These apertures 34 allow movement of the isolator relative to the base without interference between the flanges and the links. Those of skill in the art will appreciate that the amount of isolator movement or travel that can be achieved is a function of the height of the flanges, and therefore the length of the links, together with the amount of separation between the edges of the upper platform 22 and the downwardly extending flanges 30. Longer links and greater separation will allow greater isolator travel.

The links 16 are each made up of an intermediate segment which terminates at each end in a connector 40. As illustrated, the connectors 40 have a socket configuration designed to cooperate with the ball connectors 42 mounted to the fixtures 26 and 32. Together, the connectors 40 and 42 comprise a connection that permits the links to move through 360 degrees around the links' vertical orientation. Thus, the isolator 14 is able to move in any horizontal direction relative to base 12.

One preferred embodiment of the invention also makes use of an isolator travel limit system comprising first and second stop members associated with the base and isolator. As illustrated, a stop post 46 extends from the upper platform 22 and through stop aperture 48 located in the isolator upper plate 28. The stop post may be fitted with a conical bumper 50, preferably made of a suitable elastomer. The aperture 48 may also include and elastomeric bumper 52. As a result, the travel of isolator 14 is limited by the engagement of the two stop members. Those of skill in the art will appreciate that the positions of the post 46 and aperture 48 may be reversed so that the post extends down from the isolator and through the aperture located on the base.

In accordance with another preferred embodiment of the invention, a lock out system may also be employed. Again, with reference to the illustrated embodiment one or more lock pins 56 extend upwardly from the upper platform 22 and through appropriately situated lock apertures 58 in the isolator. One or more latch plates 60 are mounted to a lock out actuation lever 62 which permits movement of the latch plates to engage or disengage the lock pins 56. When engages the isolator 14 is locked in fixed position relative to the base 12.

There are important advantages associated with the present invention. One is that because of the gravitationally controlled, self centering characteristics of this suspended isolator design, there is no need for centering springs as are commonly used with most prior art isolator systems. Another advantage has to do with the specific path of travel of the isolator. As the isolator moves off its center position it not only travels horizontally, but also along an upwardly curving path. This creates an increasing resistance to further movement, or the equivalent of an "increasing spring rate" resistence, which is a desirable attribute in seat isolation systems. Still another advantage of the present invention is that there is very little resistance to movement of the isolator at or near its center point. This allows the system to be more effective in attenuating high frequency and low magnitude inputs as compared to conventional isolators using spring and shock absorber arrangements. Finally, the isolator system of the present invention has a much lower profile than conventional isolator systems.

It will be appreciated by those skilled in the art that various changes and modifications can be made to the illustrated embodiments without departing from the spirit of the present invention. All such modifications and changes are intended to be covered by the appended claims.

Claims

The invention claimed is:

1. A vehicle seat suspension apparatus comprising: a base having at least one platform; an isolator positioned above the base and including a plurality of depending side members extending to a level below the platform; and a plurality of links for suspending the isolator from the base, the links being connected to the platform and the side members of the isolator in a manner permitting the isolator to self center and move horizontally in all directions relative to the base.

2. The vehicle seat suspension apparatus of claim 1 wherein the isolator includes a pair of flanges depending from opposing sides of the plate, and the base platform is positioned below the isolator plate and between the flanges, and wherein the links connect the base platform to the flanges to thereby suspend the isolator from the base.

3. The vehicle seat suspension apparatus of claim 2 wherein each of the links comprises an intermediate segment with a ball connector at each end, the ball connectors being adapted to cooperate with socket connectors associated with the base platform and the isolator flanges.

4. The vehicle seat suspension apparatus of claim 1 further comprising a first stop member extending from one of either the base or isolator and a second stop member in the other of the base or isolator, the first and second stop members cooperating to limit the horizontal movement of the isolator.

5. The vehicle seat suspension apparatus of claim 4 wherein either or both of the stop members includes an elastomeric bumper.

6. The vehicle seat suspension apparatus of claim 4 wherein the first stop member comprises a stop post extending from the base and includes a conical elastomeric bumper.

7. The vehicle seat suspension apparatus of claim 6 wherein the second stop member comprises an aperture on the isolator plate and includes an annular elastomeric bumper.

8. The vehicle seat suspension apparatus of claim 1 further comprising a locking element located on one of either the base or isolator and a second locking element located on the other of the base or isolator, the first and second locking elements being engageable to lock the position of the isolator relative to the base.

9. The vehicle seat suspension apparatus of claim 8 wherein the first locking element comprises a lock pin extending from the base through a lock aperture on the isolator, and the second locking element comprises a movable latch plate to engage or disengage from the lock pin.

10. A vehicle seat suspension apparatus comprising: a base comprising a lower platform adapted for assembly to a vehicle and an upper platform vertically movable relative to the lower platform; an isolator plate positioned above the upper platform and having a pair of depending flanges; and a plurality of links suspending the isolator plate from the upper platform, the links being connected to the upper platform and the isolator plate flanges by means of ball and socket connections thereby permitting the isolator plate to move horizontally in all directions relative to the upper platform.

11. The vehicle seat suspension apparatus of claim 10 wherein the isolator plate flanges include openings positioned adjacent the links to accommodate the horizontal movement of the isolator plate.

12. The vehicle seat suspension apparatus of claim 11 further including a stop member extending from the upper platform through a stop aperature in the isolator plate, the stop member having a conical elastomeric bumper and the stop aperture having an annular elastomeric bumper.